Golf is presently a very popular sport which is helpful in a player's perseverance, patience and sharp attention. Golf is not only a good sport and amusement, but also a good way to establish good social relationships with others.
In a golf game which is usually held in the outdoors with widely spread grass, a golf club head often hits some hard rocks or stones exposed form beneath the grass. This, plus frequent impact of the golf club head with golf balls, makes the golf club head metal coating subject to be easily worn out, which adversely affects the beauty and use of the golf club.
In view of the fact that the golf club head is frequently used to strongly strike a golf ball, it is a common practice to coat the golf club head with suitable metal material, including sprayed and plated metal layers, to enhance and protect the beauty and hardness thereof. The plated metal layer is a protective film produced on a surface of the metal golf club head through an electrochemical reaction. In the electrochemical reaction, the metal golf club head is hung in an electrolyte and is connected to a negative electrode of a DC power source and the coating metal material is also hung in the electrolyte and is connected to a positive electrode of the DC power source. When a circuit between the two electrodes is made, the electrochemical reaction starts. The protective film so formed is very weak. As for a general sprayed coating, it can only form a protective film which penetrates into the protected metal to a limited depth. That is, the sprayed coating can only form a very thin film attached to a superficial area of the metal golf club head. Either the plated or the sprayed metal coating on the metal golf club head tends to easily peel off or become worn out when the golf club is frequently used to strike the golf ball.
It is therefore desirable to develop an effective method of coating a golf club head so a to eliminate the drawbacks from the protective layer being easily worn out or peeling off, as found in the conventional plating or spraying method for golf club heads.